origin regex

regex.js

//var org = /^https?:\/\/(?=.{1,254}(?::|$))(?:(?!\d|-)(?![a-zA-Z0-9\-]{1,62}-\.)[a-zA-Z0-9\-]{1,63}\.)*(?:(?!\d|-)(?![a-zA-Z0-9\-]{1,62}-$)[a-zA-Z0-9\-]{1,63})(:\d+)?$/;
var org = /^https?:\/\/(?=.{1,254}(?::|$))(?:(?!\d|-)(?![a-z0-9\-]{1,62}-(?:\.|:|$))[a-z0-9\-]{1,63}\b(?!\.$)\.?)+(:\d+)?$/i;

/* Origin regex explained

/^      // beginning
https?:\/\/                   // starts with http:// or https://
(?=.{1,254}(?::|$))           // the hostname chars must be within 1-254 bytes

// match one or more parts of a hostname (<part>.<part>)
(?:(?!\d|-)                   // cannot start with a digit or dash

  (?![a-z0-9\-]{1,62}-        // part cannot end with a dash
    (?:\.|:|$))               // (end of part will be '.', ':', or end of str)
  [a-z0-9\-]{1,63}\b          // part will be 1-63 letters, numbers, or dashes
    (?!\.$)                   // last part cannot end with a '.'
    \.?                       // part followed by '.' unless the last one
)+                            // one or more hostname parts

(:\d+)?                       // optional port

$/i;    // end; case-insensitive

*/


console.log("good");
console.log("https://google.com".match(org)); // good
console.log("https://hey.blahahahah.google.com".match(org)); // good
console.log("https://hey.blah-ahahah.google.com".match(org)); // good
console.log("https://localhost".match(org)); // good
console.log("https://local.host:8008".match(org)); // good
console.log("https://local-host".match(org)); // good
console.log("https://hey.blahahahah.google.c".match(org)); // good
console.log("https://aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa:1002".match(org)); // hostname short enough, port not included

console.log("\nbad should be null:");
console.log("https://local.host:8008a".match(org)); // bad port
console.log("https://-hey.blah-ahahah.google.com".match(org)); // starts with dash
console.log("https://hey.blah-ahahah.google-.com".match(org)); // part ends with dash
console.log("https://0hey.blah-ahahah.google.com".match(org)); // starts with number
console.log("https://localhost-".match(org)); // ends with dash
console.log("https://localhost.".match(org)); // no final part
console.log("https://".match(org)); // no hostname
console.log("https://aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa-ahahah.google.com".match(org)); // label too long
console.log("https://aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa--hahah.google.com".match(org)); // label too long
console.log("https://aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa-0hahah.google.com".match(org)); // label too long
console.log("https://aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa".match(org)); // hostname too long
console.log("https://aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa:1002".match(org)); // hostname too long, with port